Proposal of invasiveness score to predict recurrence and survival after curative hepatic resection for hepatocellular carcinoma

Background. Hepatocellular carcinoma (HCC) is one of the most malignant human tumors and is associated with a high incidence of postoperative recurrence. There is no generally accepted definition for HCC invasiveness. Moreover, the predictive value of the pathologic factors that reflect HCC invasiveness was previously studied as separate events, with much controversy among different study groups. in this study, we proposed an invasiveness scoring system based on the relative importance of six criteria for HCC invasiveness: portal vein invasion, intrahepatic metastasis, hepatic vein invasion, serosal invasion, absence of tumor capsule, or presence of capsular invasion. Methods. A total of 137 patients (111 male and 26 female) who underwent curative hepatectomy for HCC were included. Scoring of the six pathologic parameters was based on the clinical significance of each parameter as a single predictor for recurrence after curative resection. According to our scoring system, the patients were divided into three groups: low invasive HCC group A with a total invasiveness score 0 to 1, moderately invasive group B with a score of 2 to 4, and highly invasive group C with a total score of 5 or greater (5 to 11 points). Results. Evaluation of the current scoring system showed a significant stepwise increase in the incidence of recurrence as the invasiveness score increased. Moreover, disease-free survival was significantly different among the three groups (log rank p < 0.0001). The 1-, 3-, 5-, and 8-year disease-free survival rates were 89%, 59%, 54%, and 54% in group A; 72%, 32%, 12%, and 10% in group B; and 54%, 19%, 7%, and 0 in group C, respectively. Multivariate analysis showed that the patients of groups B and C had a significantly worse prognosis compared with those of group A (p < 0.0001). Conclusions. The current scoring system can classify HCCs into three invasive categories and predict more accurately recurrence and disease-free survival after curative hepatectomy compared with any single invasive parameter previously proposed. Moreover, this system can be used as a therapeutic guide during and after the surgical decision making.